first: calm down. no, you didn't hurt your device.
second: read the whole threads before you start flashing the first time.
this is a good place to start:
http://forum.ppcgeeks.com/showthread.php?t=32382
List of things to try:
1. did you update your SPL? if not, reflash back to the original rom (see below) and start over.
2. Did you try a hard reset (hold down both left and right softmenu keys and hit reset, then press "r" when prompted)
3. if you did, did you try flashing back to your original rom? Hold down the power + camera keys and reset, it will pull up a multi-colored screen from which you can plug in the USB and flash a new ROM.
If nothing there helps, please post *exactly* what you did and we'll see if we can help... but before you do that, make sure you have read and tried to find the answer yourself. The details are all over this forum and there are hundreds of useful threads that could help. Your thread title is about as helpful as a blank wall, my friend, because it says nothing about what you actually need.
Welcome to the fun world of custom firmware =] You'll find it's a lot of fun, but you need to do the due diligence and do some research first.
Good luck! it'll all be fine!
Richard